Our overall approach is brings together a multidisciplinary team to determine the role of obesity in the development of benign prostatic hyperplasia (BPH). The research team has expertise in biological modeling of urogenital tract disease, epidemiology, and medicine, with special emphasis on model development and clinical manifestations of obesity, inflammation, and metabolic stress. The overall hypothesis is that benign hyperplastic growth of the prostate and associated inflammatory responses are influenced by obesity and diet. We further hypothesize that some of these changes may be reversed by appropriate dietary or surgical interventions, while others may become fixed. The project is broken into three aims, all centered on the links between BPH, inflammation, and obesity. The first aim will test prostatic histopathologic changes, immune/inflammatory cell recruitment and systemic inflammatory marker changes induced in wild type, leptin receptor knockout (ob/ob) and low density lipoprotein receptor knockout (LDLR-/-) C57/BL6 mice by high fat/high sucrose or high fat/high corn starch dietary regimens. Our preliminary data demonstrate that these models undergo prostatic changes consistent with aspects of human BPH. The second aim will examine the reversibility of these phenotypic and inflammatory changes using caloric restriction and Roux-en-Y gastric bypass (RYGB) surgery. These techniques will be applied to the mouse models at specific times in the development of inflammation and hyperplasia to determine which aspects of the disease process can be reversed by altering dietary habits. The third aim will take advantage of a NIDDK supported, prospective epidemiologic study of men with BPH (the Nashville Men's Health Study) to determine if blood and urine biomarkers of obesity and inflammation and insulin expression and sensitivity are associated with levels of prostate tissue inflammation or BPH symptom progression over time. Specific Aims one and two are designed to determine the role of obesity in the induction and maintenance of specific markers of prostatic hyperplasia. Aim three extends these concepts to obesity, prostate tissue inflammation, and BPH progression in humans. The integration of these aims across mouse models and human epidemiology with overlapping biomarker panels will ground the mouse models to the clinical realities of human BPH, while also developing an understanding of the mechanisms underlying disease pathogenesis.